Question

在JavaFX中定义TableView时是否有办法限制行数？我的情况是刷新TableView而不清除，只是覆盖行1中的值。如果我没有清除Tableview，则值只是附加而不是覆盖。

我想只查看前30行。

Answer 1

您可以使用FilteredList来限制显示的行数。 Makery tutorials有关于如何使用FilteredList的更多信息。

例如，限制TableView显示列表中的前三项：

FilteredList<Person> filteredData = new FilteredList<>(
    data,
    person -> data.indexOf(person) < 3
);

此解决方案假设每个项目都是唯一的。

示例代码

import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.collections.*;
import javafx.collections.transformation.*;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.control.cell.PropertyValueFactory;
import javafx.stage.Stage;

public class TableViewSample extends Application {

    private static final int MAX_ITEMS = 3;

    private final TableView<Person> table = new TableView<>();
    private final ObservableList<Person> data =
        FXCollections.observableArrayList(
            new Person("Jacob", "Smith"),
            new Person("Isabella", "Johnson"),
            new Person("Ethan", "Williams"),
            new Person("Emma", "Jones"),
            new Person("Michael", "Brown")
        );
    FilteredList<Person> filteredData = new FilteredList<>(
            data,
            person -> data.indexOf(person) < MAX_ITEMS
    );
    SortedList<Person> sortedData = new SortedList<>(filteredData);

    public static void main(String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage stage) {
        TableColumn<Person, String> firstNameCol = new TableColumn<>("First Name");
        firstNameCol.setCellValueFactory(new PropertyValueFactory<>("firstName"));
        table.getColumns().add(firstNameCol);

        TableColumn<Person, String> lastNameCol = new TableColumn<>("Last Name");
        lastNameCol.setCellValueFactory(new PropertyValueFactory<>("lastName"));
        table.getColumns().add(lastNameCol);

        sortedData.comparatorProperty().bind(table.comparatorProperty());

        table.setItems(sortedData);

        stage.setScene(new Scene(table));
        stage.show();
    }

    public static class Person {
        private final SimpleStringProperty firstName;
        private final SimpleStringProperty lastName;

        private Person(String firstName, String lastName) {
            this.firstName = new SimpleStringProperty(firstName);
            this.lastName = new SimpleStringProperty(lastName);
        }

        public String getFirstName() {
            return firstName.get();
        }

        public void setFirstName(String firstName) {
            this.firstName.set(firstName);
        }

        public String getLastName() {
            return lastName.get();
        }

        public void setLastName(String lastName) {
            this.lastName.set(lastName);
        }
    }
}

如何在javafx中限制TableView的行

1 个答案: